Battery management system (BMS) is an important part of the Electric Vehicle (EV). It protects the battery system from damage, predicts and increases battery life, and maintains the battery system in an accurate and reliable operational condition. The BMS performs several tasks such as measuring the system voltage, current and temperature, the cells state of charge (SoC), state of health (SoH), and remaining useful life (RUL) determination, protecting the cells, thermal management, controlling the charge/discharge procedure, data acquisition, communication with on-board and off-board modules, monitoring and storing historical data and the most important task is the cell balancing. Imbalance of cells in battery systems is very important matter in the battery system life. Because without the balancing system, the individual cell voltages will drift apart over time. The capacity of the total pack will also decrease more quickly during operation′ then fail the battery system. As mentioned in cited references below, currently, the most common methods of battery management are based on passive and active cell balance or equalization (such as bypass circuits and potential conversion), using series connection or using daisy chain connection, and the connections of batteries for all the cases cited are fixed at initial of manufacture. However, none of these methods cannot access individual battery subset or single battery for measuring, monitoring and balancing, and compensation. For example, the battery management units of Kawahara et al (US 2011/0313613), Nojima et al (U.S. Pat. No. 8,655,553 B2), Gorbold et al (U.S. Pat. No. 7,859,223 B2), Poehler et al (WO 2013143754) and all other cited inventors cannot achieve this “arbitrary and automatic connection”. Here a brief comparison is given in batble below (numbers in [xxx] are paragraph numbers in cited prior arts, such as [K0088] is for paragraph 0088 in Kawahara's):
CatalogsPrior ArtsThis InventionFunctions toCharging, discharging and monitoringSame as leftbe achievedbatteries, thermal managementSystemBatteries, cell control unit, batteryBatteries, connection controller,componentsmanagement unit, charger, inverter,system controller, charger, load &Voltage meter and SOC detectorserve pack, monitoring meters,[Kawahara FIGS. 1, 2]hole-net thermal bedPower supply, DPS, monitoringcomponent, storage component, userinterface [Nojima FIG. 1]battery cells 10, 12, 14, 16, 18,monitoring device, 30, 32, 34,3 6, 38, andcontroller 70 [Gorbold FIG. 1; Poehler FIG. 2]SystemKawahara FIGS. 1, 2; Gorbold FIG. 1;Construction in FIG 1 is obviouslyconstructionsNojima FIG. 1; Poehler FIG. 2.and completely different form the 3prior artsBattery“two battery modules 112 a, 112 b inBy using invented connectionconnectionseries, each battery module includingcontroller, batteries canfour batteries 111 electrically connectedautomatically re-combined in anyin series . . . , actually, approximatelykinds of (i.e. arbitrarily given100 to approximately 200 batteriesnumber of cells) parallel or any111 are mounted and electricallykinds of series or any kinds ofconnected in series or in series andmixed series-parallel connection,parallel” [K0088]--- these connectionsduring operationare fixed at initial of building, andcannot be changed during operation.Number of cells in in series and parallelconnection cannot be arbitrarily given.“As can be seen from FIG. 1, the battery“daisy chain” is not used in thismonitors are arranged in a daisy chain.”invention[G005] (i.e. Gorbold: BRIEFDESCRIPTION paragraph 005); “Thisloop connection may be referred to asthe “daisy chain connection”“[K0097]OperationThe cell control unit 120 includes aOnly one connection controllercontrolplurality of battery managementcontrolled by microprocessor (orunits [K0091-K0094]computer)Driver circuitsCircuit of control unit consists of daisyconnection controller circuitchain us shown in Kawahara FIG. 3 andconsists of switch matrix as shownGorbold FIG. 1in FIG 3 and FIG 8(a)Components“. . . groups of cells 10, 12, 14, 16, 18Only one shared monitoringsharingand 20 respectively . . . Each groupdevice for all battery cells orof cells is associated with a respectivesubsets by using connectionbattery monitoring device, 20, 32,controller to choose individual cell34, 36, 38, and 40” [G001]; “ . . .or subsetbattery management units121 a,121 b . . .”[K0094 - 0094, K0097, K01060,K0107]. --- means all of them needmultiple individual monitoringdevicesNumber of“A plurality of temperature sensors (notOnly need one at center or twoSensorsillustrated) for detecting the temperaturesensors at center and outsideof the battery pack is installed”because hole-new thermal bed[K0090]makes the temperature almostuniform and don't need more.potential“In this embodiment, the potentialNo need of “potential conversion”conversionconversion (level shifting) is performedon the input side of the signalinput/output circuits” [K0106]bypass circuit“For this reason, each of the batteryNo need of “bypass circuit”management units 121 a, 121 b includesa bypass circuit electrically connected inparallel between the respectiveterminals of thebatteries 111 constituting thecorresponding batterymodules 112 a, 112b” [K0107]
More comparisons will be described in paragraph [20] in section of “Detail Description of the Invention”.